// UTF-8
/**
 * scrollsmoothly.js
 * Copyright (c) 2008 KAZUMiX
 * http://d.hatena.ne.jp/KAZUMiX/20080418/scrollsmoothly
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 * 
 * 隴厄ｽｴ隴�ｽｰ陞ｻ�･雎�ｽｴ
 * 2009/02/12
 * 郢ｧ�ｹ郢ｧ�ｯ郢晢ｽｭ郢晢ｽｼ郢晢ｽｫ陷亥現窶ｲ騾包ｽｻ鬮ｱ�｢陝ｾ�ｦ闕ｳ鄙ｫ竊鍋ｸｺ�ｪ郢ｧ蟲ｨ竊醍ｸｺ�ｽ�ｴ陷ｷ蛹ｻ�ｽ隰門雀陌夂ｹｧ蜑�ｽｿ�ｮ雎�ｽ｣
 * 2008/04/18
 * 陷茨ｽｬ鬮｢
 *
*/

(function(){
   var easing = 0.25;
   var interval = 20;
   var d = document;
   var targetX = 0;
   var targetY = 0;
   var targetHash = '';
   var scrolling = false;
   var splitHref = location.href.split('#');
   var currentHref_WOHash = splitHref[0];
   var incomingHash = splitHref[1];
   var prevX = null;
   var prevY = null;

   // 郢晏ｳｨ縺冗ｹ晢ｽ･郢晢ｽ｡郢晢ｽｳ郢晞メ�ｪ�ｭ邵ｺ�ｿ髴趣ｽｼ邵ｺ�ｿ陞ｳ蠕｡�ｺ�ｽ蜃ｾ邵ｺ�ｫinit()郢ｧ雋橸ｽｮ貅ｯ�｡蠕娯�郢ｧ
   addEvent(window, 'load', init);

   // 郢晏ｳｨ縺冗ｹ晢ｽ･郢晢ｽ｡郢晢ｽｳ郢晞メ�ｪ�ｭ邵ｺ�ｿ髴趣ｽｼ邵ｺ�ｿ陞ｳ蠕｡�ｺ�ｽ蜃ｾ邵ｺ�ｮ陷�ｽｦ騾
   function init(){
     // 郢晏｣ｹ�ｽ郢ｧ�ｸ陷�ｽﾎ懃ｹ晢ｽｳ郢ｧ�ｯ邵ｺ�ｫ郢ｧ�､郢晏生ﾎｦ郢晏現�帝坎�ｭ陞ｳ螢ｹ笘�ｹｧ
     setOnClickHandler();
     // 陞溷､慚夂ｸｺ荵晢ｽ臥ｹ晏｣ｹ�ｽ郢ｧ�ｸ陷�ｽﾎ懃ｹ晢ｽｳ郢ｧ�ｯ闔牙･窶ｳ邵ｺ�ｧ陷ｻ�ｼ邵ｺ�ｳ陷�ｽｺ邵ｺ霈費ｽ檎ｸｺ貅ｷ�ｴ陷ｷ
     if(incomingHash){
       if(window.attachEvent && !window.opera){
         // IE邵ｺ�ｮ陜｣�ｴ陷ｷ蛹ｻ�ｽ邵ｺ�｡郢ｧ�ｽ笆ｲ邵ｺ�ｨ陟包ｿｽ笆ｲ邵ｺ�ｦ邵ｺ荵晢ｽ臥ｹｧ�ｹ郢ｧ�ｯ郢晢ｽｭ郢晢ｽｼ郢晢ｽｫ
         setTimeout(function(){scrollTo(0,0);setScroll('#'+incomingHash);},50);
       }else{
         // IE闔会ｽ･陞滓じ�ｽ邵ｺ譏ｴ�ｽ邵ｺ�ｾ邵ｺ�ｾGO
         scrollTo(0, 0);
         setScroll('#'+incomingHash);
       }
     }
   }

   // 郢ｧ�､郢晏生ﾎｦ郢晏現�帝恆�ｽ陷邵ｺ蜷ｶ�矩ｫ｢�｢隰ｨ�ｰ
   function addEvent(eventTarget, eventName, func){
     if(eventTarget.addEventListener){
       // 郢晢ｽ｢郢郢晢ｽｳ郢晄じﾎ帷ｹｧ�ｦ郢ｧ�ｶ
       eventTarget.addEventListener(eventName, func, false);
     }else if(window.attachEvent){
       // IE
       eventTarget.attachEvent('on'+eventName, function(){func.apply(eventTarget);});
     }
   }
   
   function setOnClickHandler(){
     var links = d.links;
     for(var i=0; i<links.length; i++){
       // 郢晏｣ｹ�ｽ郢ｧ�ｸ陷�ｽﾎ懃ｹ晢ｽｳ郢ｧ�ｯ邵ｺ�ｪ郢ｧ蟲ｨ縺帷ｹｧ�ｯ郢晢ｽｭ郢晢ｽｼ郢晢ｽｫ邵ｺ霈披雷郢ｧ
       var link = links[i];
       var splitLinkHref = link.href.split('#');
       if(currentHref_WOHash == splitLinkHref[0] && d.getElementById(splitLinkHref[1])){
         addEvent(link, 'click', startScroll);
       }
     }
   }

   function startScroll(event){
     // 郢晢ｽｪ郢晢ｽｳ郢ｧ�ｯ邵ｺ�ｮ郢晢ｿｽ繝ｵ郢ｧ�ｩ郢晢ｽｫ郢昜ｺ･陌夊抄諛奇ｽ定ｰｿ�ｺ邵ｺ
     if(event){ // 郢晢ｽ｢郢郢晢ｽｳ郢晄じﾎ帷ｹｧ�ｦ郢ｧ�ｶ
       event.preventDefault();
       //alert('modern');
     }else if(window.event){ // IE
       window.event.returnValue = false;
       //alert('ie');
     }
     // this邵ｺ�ｯ陷ｻ�ｼ邵ｺ�ｳ陷�ｽｺ邵ｺ諤懶ｿｽ邵ｺ�ｫ邵ｺ�ｪ邵ｺ�｣邵ｺ�ｦ郢ｧ
     setScroll(this.hash);
   }

   function setScroll(hash){
     // 郢昜ｸ翫Ε郢ｧ�ｷ郢晢ｽ･邵ｺ荵晢ｽ臥ｹｧ�ｿ郢晢ｽｼ郢ｧ�ｲ郢晢ｿｽ繝ｨ髫補悪�ｴ邵ｺ�ｮ陟趣ｽｧ隶灘生�堤ｹｧ�ｲ郢晢ｿｽ繝ｨ邵ｺ蜷ｶ�
     var targetEle = d.getElementById(hash.substr(1));
     if(!targetEle)return;
     //alert(scrollSize.height);
     // 郢ｧ�ｹ郢ｧ�ｯ郢晢ｽｭ郢晢ｽｼ郢晢ｽｫ陷井ｺ･�ｺ�ｧ隶灘生�堤ｹｧ�ｻ郢晢ｿｽ繝ｨ邵ｺ蜷ｶ�
     var ele = targetEle;
     var x = 0;
     var y = 0;
     while(ele){
       x += ele.offsetLeft;
       y += ele.offsetTop;
       ele = ele.offsetParent;
     }
     var maxScroll = getScrollMaxXY();
     targetX = Math.min(x, maxScroll.x);
     targetY = Math.min(y, maxScroll.y);
     targetHash = hash;
     // 郢ｧ�ｹ郢ｧ�ｯ郢晢ｽｭ郢晢ｽｼ郢晢ｽｫ陋帶㊧�ｭ�｢闕ｳ�ｭ邵ｺ�ｪ郢ｧ蟲ｨ縺帷ｹｧ�ｯ郢晢ｽｭ郢晢ｽｼ郢晢ｽｫ鬮｢蜿･�ｧ
     if(!scrolling){
       scrolling = true;
       scroll();
     }
   }

   function scroll(){
     var currentX = d.documentElement.scrollLeft||d.body.scrollLeft;
     var currentY = d.documentElement.scrollTop||d.body.scrollTop;
     var vx = (targetX - currentX) * easing;
     var vy = (targetY - currentY) * easing;
     var nextX = currentX + vx;
     var nextY = currentY + vy;
     if((Math.abs(vx) < 1 && Math.abs(vy) < 1)
       || (prevX === currentX && prevY === currentY)){
       // 騾ｶ�ｮ隶灘雀�ｺ�ｧ隶灘姓�ｻ蛟ｩ�ｿ莉｣竊楢崕�ｰ鬩墓鱒�邵ｺ�ｦ邵ｺ�ｽ笳�ｹｧ閾･�ｵ繧�ｽｺ
       scrollTo(targetX, targetY);
       scrolling = false;
       location.hash = targetHash;
       prevX = prevY = null;
       return;
     }else{
       // 驛｢�ｰ郢ｧ鬘假ｽｿ譁撰ｼ
       scrollTo(parseInt(nextX), parseInt(nextY));
       prevX = currentX;
       prevY = currentY;
       setTimeout(function(){scroll()},interval);
     }
   }
   
   function getDocumentSize(){
     return {width:Math.max(document.body.scrollWidth, document.documentElement.scrollWidth), height:Math.max(document.body.scrollHeight, document.documentElement.scrollHeight)};
   }

   function getWindowSize(){
     var result = {};
     if(window.innerWidth){
       var box = d.createElement('div');
       with(box.style){
         position = 'absolute';
         top = '0px';
         left = '0px';
         width = '100%';
         height = '100%';
         margin = '0px';
         padding = '0px';
         border = 'none';
         visibility = 'hidden';
       }
       d.body.appendChild(box);
       var width = box.offsetWidth;
       var height = box.offsetHeight;
       d.body.removeChild(box);
       result = {width:width, height:height};
     }else{
       result = {width:d.documentElement.clientWidth || d.body.clientWidth, height:d.documentElement.clientHeight || d.body.clientHeight};
     }
     return result;
   }
   
   function getScrollMaxXY() {
     if(window.scrollMaxX && window.scrollMaxY){
       return {x:window.scrollMaxX, y:window.scrollMaxY};
     }
     var documentSize = getDocumentSize();
     var windowSize = getWindowSize();
     return {x:documentSize.width - windowSize.width, y:documentSize.height - windowSize.height};
   }
   
 }());